1. Field of the Invention
The present invention relates to a reference voltage generation circuit generating a reference voltage and a semiconductor memory including the reference voltage generation circuit.
2. Related Art
In order to read out information stored in a ferroelectric memory or the like, a sense amplifier compares a voltage read out from a memory cell to a bit line with a voltage (reference voltage) of a reference bit line to sense a voltage difference between both voltages. For example, the sense amplifier determines to be “HIGH” when the voltage read out to the bit line is higher than the reference voltage and determines to be “LOW” when the voltage read out to the bit line is lower than the reference voltage. It is necessary to provide a circuit for generating an appropriate reference voltage in order to conduct a correct sense operation.
D. Takashima et al., “A 76 mm2 8 Mb chain Ferroelectric memory” (IEEE J. solid-state circuits, Vol. 36, No. 11, pp. 1713-1720, November 2001.) discloses a reference voltage generation circuit which adjusts a voltage Vdc at one end of a capacitor to control a voltage level of the reference bit line.
However, in the above document, it is necessary to provide another power circuit in order to adjust the voltage Vdc. This causes to increase an area of the circuit.